The long-term objective is to be able to regulate abnormal growth processes that are related to somatomedins. Since somatomedins are the major stimulators of bone formation, they offer real promise in the therapy of post-menopausal osteoporosis. They may also be used to stimulate bone formation around prosthetic joints. The stimulatory properties of somatomedins may also be important in hastening a wound healing. Because of their short half-life in order to use the somatomedins an appropriate delivery system must be developed. Since they are transported in plasma bound to a carrier protein the latter will be utilized. Since this protein will also block the growth promoting effects of somatomedin, it will also be useful to suppress the growth of those tumors that produce somatomedin and autostimulate their own growth. The specific aims of this project will be to purify to homogeneity the human serum carrier protein, characterize it and produce antibodies to it.